Can Cannabis Help Prevent Dementia?

By Pat Anson, PNN Editor

People use cannabis for a variety of reasons. Some use it to relieve pain. Others use it to help them sleep, improve their appetite, or reduce anxiety and stress. Still others use cannabis because it makes them feel good.

A new study suggests there’s another unexpected benefit from consuming cannabis, especially when it’s used recreationally: It may help middle-aged adults ward of dementia.

Researchers at SUNY Upstate Medical University looked at health survey data that assessed the subjective cognitive decline (SCD) of over 4,700 U.S. adults between the ages of 45 and 64. Memory loss and confusion are symptoms of SCD, which is considered an early sign of dementia.

To their surprise, researchers found that participants who only used cannabis recreationally had significantly lower risk of SCD – as much as 96% less risk compared to non-users. Those who used cannabis for medical reasons or combined it with recreational use also had lower odds of SCD, but the difference was not statistically significant.

“We found that non-medical cannabis use was significantly associated with reduced odds of SCD in comparison to non-users. Several factors might explain this observation. Non-medical use of cannabis often contains THC, which has a psychoactive component that creates the ‘high’ sensation. Whereas CBD is non-psychoactive and often used for anxiety and chronic pain management,” the SUNY research team recently reported in the journal Current Alzheimer Research.

One likely reason for the disparity in SCD between recreational and medical users is that those who consume cannabis for health reasons may have comorbid medical conditions – such as diabetes, hypertension, cardiovascular disease and musculoskeletal disorders -- that raise their risk of dementia.

Another consideration is sleep. One of the primary reasons people use cannabis is to help them fall asleep faster and stay asleep longer. Recreational use of cannabis has the added benefit of improving sleep quality. A recent study found that insomnia is associated with a 51% higher risk of dementia risk.

The frequency of cannabis use and whether it was smoked, vaped or ingested had no significant connection to SCD risk.

Although the study found no direct cause-and-effect relationship between cannabis, SCD and dementia, researchers think it’s worth exploring further. More than six million Americans have Alzheimer’s disease or some form of dementia, a number that’s expected to double by 2050. 

“Despite the advancement of medicine and technology, dementia remains incurable and non-preventable. While some medications can slow symptom progression, they are only effective if started during early stages and cannot reverse its course,” SUNY researchers concluded. “Given the widespread use of cannabis in the U.S., it is imperative to pursue further research to understand the mechanism underlying the reduced odds of SCD among non-medical cannabis users.”